The present invention relates to a vacuum cleaner beater brush assembly provided at a nozzle of a vacuum cleaner, and more particularly to a vacuum cleaner beater brush roller of the beater brush assembly having the simple structure capable of facilitating the assembling thereof and preventing a damage, such as a crack, of the roller during fitting the rotating axles thereto.
Conventionally, a vacuum cleaner comprises, as shown in FIG. 1, a main body 1 having a chamber for collecting dirt, a suction nozzle 4 for sucking the dirt therethrough, a flexible hose 2 connected to a connector of the main body 1, a pipe 3 or a handle connected to the suction nozzle 4, said hose 2 and said pipe 3 connected to each other and adapted for guiding the dirt, having sucked by the nozzle 4 from the surface being cleaned, to the main body 1.
As shown in FIG. 2 which is an exploded perspective view representing the structure of a nozzle of a vacuum cleaner in accordance with the prior art, the suction nozzle 4 generally comprises a bottom casing 5, and a rotatable beater brush assembly 6 rotatably mounted to the bottom casing 5 and adapted for agitating the surface being cleaned, such as a carpet or the like, for improved removal of dirt therefrom. A drive motor 8 is mounted to the bottom casing 5 at a back position spaced apart from the beater brush assembly 6 for generating power for driving the beater brush assembly 6, and a cog belt or timing belt 7 is disposed in order to connect the beater brush assembly 6 to the drive motor 8 so that the driving power is transmitted form the drive motor 8 to the beater brush assembly 6. The suction nozzle 4 is also provided with an air guider 9 for guiding the air including dirt having sucked by the nozzle 4, a spring 10 for controlling the height, a connector 11 rotatably mounted to the air guider 9 in order to be connected to a free end of the pipe 3 so that the air including dirt having sucked by the nozzle 4 is guided to the pipe 3 thereby. A bumper 12 is provided to the nozzle 4 for absorbing the outside shock, and an electric switch 13 for switching the electric power for driving the drive motor 8. There is provided in the nozzle 4 an upper casing 14 mounted onto the bottom casing 5 in order to cover the enclosures enclosed in the casing provided by the upper and bottom casings 5 and 14, a switching button 15 connected to the switch 13 and adapted to be pushed by the operator for switching the switch 13, a cover 16 for covering the upper casing 14, and an electric code 17 for supplying electric power from the outside power source to the drive motor 8 by way of the switch 13.
Among the above elements of the nozzle 4, the rotating beater brush assembly 6 which is related to the present invention is generally provided with a helical brush strip having a plurality of brush elements or brush bundles and a helical beater strip having a plurality of rigid beater projections, both strips adapted for agitating the surface being cleaned such as a carpet, for improved removal of dirt therefrom.
A representative example of such a beater brush assembly combined with a nozzle of a vacuum cleaner is that disclosed in John B. Lyman U.S. Pat. No. 4,429,430 which is referred to this invention in conjunction with the drawings, FIGS. 2 to 4. As shown in the drawings, the rotatable beater brush assembly 6 is provided with a rotatable cylindrical dowel or roller 20. The roller 20 carries a plurality of helical undercut channels 21 and 21' formed on the circumferential surface thereof in order to each receive a brush strip 23 and a beater strip 25 therein. The brush strip 23 has a plurality of brush bundles 22 secured thereto and spaced apart from each other for agitating the surface being cleaned such as a carpet upon rotation of the beater brush assembly 6. Also, the beater strip 25 comprises a plurality of relatively rigid projections 24 which are engaged with the surface being cleaned upon rotation of the beater brush assembly 6. The undercut channels 21 and 21', the brush strip 23 and the beater strip 23, both strips received in said undercut channels 21 and 21', are provided with complementary cross sections for retention in the channels 21 and 21' against centrifugal forces developed in rotation of the roller 20 about the axis thereof.
Also, the beater brush roller 20 is generally manufactured by relatively high strength maples, a kind of gingkos, and provided with a pair of rotating axles 26 and 26' inserted into opposite ends thereof in order to project therefrom and support the rotation thereof. Each of the rotating axles 26 and 26' is provided with a knurling machined portion 26a, 26'a at a center thereof, respectively, so that the axles 26 and 26' are fixed to the roller 20 not to move with respect to the roller 20 by virtue of the knurling machined portions 26a and 26'a thereof on fitting to opposite ends of the roller 20.
Furthermore, the rotatable beater brush assembly 6 has a support pulley 27 engaging with an end of the roller 20 in order to closely face thereto. The other end of the roller 20 engages with a sprocket comprising a first portion or ring flange 28 closely connected to one end of the roller 20 and having a belt retaining flange, and a second portion or gear pulley 29 engaging with the ring flange 28 and having teeth formed integrally therewith for engaging with the timing belt 7 so that the beater brush roller 20 is driven to rotate by virtue of rotation of the gear pulley 29.
An edge brush assembly 31 is provided outboard of the gear pulley 29 and includes a plurality of brush tufts 30 and an integral beater bar on the circumferential surface thereof, respectively. The brush assembly 31 is secured to the other end of the roller 20 by means of a pair of set screws 32, under the condition that the ring flange 28 and the gear pulley 29 are interposed between the brush assembly 31 and the roller 20, respectively. Also, a pair of bearing mounts 34 and 34' having an oil-filled bronze sleeve bearing, respectively, engage with the axles 26 and 26' at the opposite ends of the roller 20 in order to rotatably support the rotation of the roller 20, and a pair of washers 33 and 33' are interposed between both ends of the roller 20 and the bearing mounts 34 and 34'.
In assembling the above beater brush assembly 6, the support pulley 27 and the ring flange 28 are first fixed to the opposite ends of the roller 20. Thereafter, one bearing mount 34' is connected to the end of the roller 20 by fitting the axle 26' of the roller 20 into the oil-filled sleeve bearing of the bearing mount 34' under the condition that the washer 33' is disposed between the front end of the sleeve bearing of the bearing mount 34' and the depressed side surface of the end of the roller 20, while the gear pulley 29 and the edge brush assembly 31 are sequentially inserted onto the projection of the other axle 26 onto which the ring flange 28 has been mounted. Then, the gear pulley 29 and the assembly 31 are secured to the other end of the roller 20 by means of the screws 32. The other bearing mount 34 is then connected to the other end of the roller 20 by fitting the axle 26 of the roller 20 into the oil-filled sleeve bearing of the bearing mount 34.
In accordance, the above rotatable beater brush assembly 6 rotates by means of the drive force transmitted from the drive motor 8 to the gear pulley 29 by way of the timing belt 7, thereby allowing the brush bundles 23 of the brush strip 23 and the rigid projections of the beater strip 25 provided on the circumferential of the roller 20 to agitate the surface being cleaned, such as a carpet or the like, for improved removal of dirt therefrom.
Also, rotation of the edge brush assembly 31 accompanies the rotation of the roller 20 so that the brush tufts 30 and the integral beater bar provided on the circumferential surface of the assembly 31 efficiently agitate the edge of the surface being cleaned, for improved removal of dirt.
However, this type of beater brush roller has disadvantages in that it comprises a cylindrical body provided with the undercut channels 21 and 21' on the circumferential surface thereof each for receiving the brush strip 23 having the brush bundle 22 or the beater strip 25 having the rigid projections 24, so that it has the relatively complex structure resulting in difficulty of the assembling thereof, also a lengthwise crack of the roller 20, made of the relatively high strength maples, easily occurs in fitting portions thereof, at which the axles 26 and 26' are forcedly fitted thereto in order to prevent from moving with respect to the roller 20 by means of the knurling machined portions of the axles 26 and 26', the crack of the roller 20 is due to the forced fitting power.